Selective signaling system.



, UNITED STATE JOHN' J. LYNG,

OF YONKERS,

OF NEW YORK, N. Y., A C

s PATENT oEEicE.

NEW YORK, ASSIGNOR T WESTERN ELECTRIC ORPORATION OF ILLINOIS.

COMPANY,

SELECTIVE SIGNALIG SYSTEM.

' and' useful Improvement in Selective Signalin Systems, of which the following is a tali clear, concise. and exact description;

This invention relates to signaling systems and more particularly to a telephone si naling system of the class wherein each ol a lurality of stations on one lline has a signa ing' device connected with the line wires which may be selectively operated, each of said signaling devices being operable independently of the other devices on the same line. l

The object of the vinvention is to provide a selective signaling system in which the signaling device of any party on the line may be operated instantaneously and selectively lin response to the operation of a calling'key or` switch at a main or sending station.A V

In a] system embodying this invention there is located' at` each waystation on the line a localj signal the circuit of which is controlled by .two relays, the relays of each pair' being severally operable by currents over diler'entv circuits including the two line wires. The system depends for its selectivity of operation upon the positive operation or non-operation of these relays, that is to say,the combination o the apparatus and circuits is such that no two sets or pairs of relays may be operated simultaneously. `o provide for this the relays are made to respond to different strengths of currents, those operable over one of the circuits requiringh currents of constantly-inc1easing strengA from' the sending station toward the end of the line, while those relays operable over the other of said circuits will respond to currents of decreasing strength from the calling station outward, the relay in this circuit located at the end farthest from the calling station being operable with the minimum amount of current.

The drawing is a diagram of a circuit and apparatus embodying vthis invention.

Referring-to the drawing, 5 and 6 designate line wires with which are connected a sending or calling station A and a plurality of waystations B, C, D, E, F and G respectively. Located at each ot' the way- Specification of Letters Patent. Application led January 31, 1913.

i .stations B, C, D,

Patented June 23, 1914. serial No. 745.373.

E, F and G is a pair of relays ll and 15 controlling armatures 16 and 17 respectively. The relay 14'- is connected in a bridge of the line wires 5 and 6 which bridge also includes resistances 20, 20 while the relay 15 is in a circuit to ground including a resistance 2l, the circuit of said relay l5 being -controlled by the armature 16 of the relay 14.-. The armature of the relay 15 controls a local circuit including a source of energy 25 and a signal 26. The

.resistances 20, 2O in series with the relays 14, 14:, although of the same value for each individual station, are tapered in value from the calling station A toward the end of the line remote from the station, the resistances near the calling station being of low value and Vgradually increasing to a maximum value at the station farthest from the calling station... The resistances 21 in series with-the relays 15, 15 are likewise tapered in value from the calling station toward the l end of the line remote fromr the calling station but in an inverse order to the resist'- ances 20, 20-that is, the resistance 21 of maximum value will be located at stationB or that nearest the calling station A, the minimum value of 21 being at the end of the line remote from said station A. Certain numerical values are given these two groups oi'- resist-ances for purposes of illustration but itis to be understood that the application is not limited to the values given.

Located at the calling station A are a plu'- rality of switch keys-30,l 31, 32, 33, 34 and 35 corresponding in number to the waystation's on the line. Each of said switch keys 30,31, 32, 33, 34 and 35 is wired to connect battery with the line wires for operating the relays, a battery 36 for operating the bridged relays being connected across the line wires 5 and 6 through a regulating resistance 38 `divided into steps controlled by said switch keys. A battery 40 for operating the relays over the two line wires to ground is connected from the center point of a high resistance 4l bridging the line through a resistance 42 di`- vided into steps regulatedby said switching keys 30, 3l, 32, 33, 34 and 35. The wiring of the switch keys 30, 31, 32, 33, 34 and35, the batteries 36 and 40 and the resistances 38' and 42 is such that the operation of any key will send current over the two circuits in the proper amounts and directions to operate only a particular pair of relays 14, 15.

n This will be more clearly seen by following the operation in signaling one or more of the stations on the line.

Assuming that it is desi-red to operate the signal 26 at .station B. This will be accolaplished by the operation of the key 80 which will close its contacts 50 and 51 to complete two circuits, one being from the one side of the battery 36, conductor 52, line wire 5, the bridged relays 14, 14, line ire 6, conductor 53, the total of resistance 38, contact 50 of key 30 and conductor 54 to the opposite side of battery 36. Only sufficient current will flow in this path to operate the relay 14 at station B. The other circuit cl sed by key Y 30 will be from ground at 55, through contact 51 of key 30, conductor 57, battery 40 to the middle point of resistance 41 to line wires 5 and 6 over which the current passes in parallel to the middle point of the relay 14 at station B, through contact 58 closed by said relay 14 at the station B, conductor 59, relay 15 at station B, and the resistance 21 to ground. The full strength of the battery flows through this path but since the-relay 14 at station B is the only one operated over the path rst traced, there will be no circuit for any of the other relays 15. The operation of the relay 15 at station B will close the local circuit including the local signal 26 at this station B. In a like manner, if it is desired to signal any other Istation on the line, the key corresponding to this station will be depressed to apply the proper current combinations to the two circuits to operate only a selected pair of relays.

It will be noted that although all of the relays 14 at stations preceding any station on the line will be operated by the current which will operate the relay 14 at a selected station, the current in the path over which the relay 15 at the selected station is operated will be of suiicient strength only to operate that relay and the relays 15 at all succeeding stations beyond the selected one, thus making it impossible to call more than one station at a time.

While the relays are illustrated as the polarized type, the invention may be worked vwith non-polarized relays, but it will be obvious that by the use of the polarized relays a system of much larger capacity can be obtained than is possible with non-polarized relays. The method of wiring the switch keys when both polarities of battery are used for obtaining a selection will readily suggest itself to any one skilled in the art to which this invention pertains.

I claim:

1. `In a'party line selective signaling system, a pair of line wires, a sending station and a plurality of waystations connected therewith, a pair of relays located at each of said waystations, the relays of each pair `Limusay being severally operable by currents over a metallic andgrounded circuit respectively including said line wires, means for rendering the relays of each pair responsive to current combinations'of particular strengths over the two circuitsa signal at each of said waystations controlled by the relays thereat, and means at the calling station for impressing upon the circuits vthe current vthe sending station for simultaneously applying currents to the two circuits of strengths to operatea selected pair of relays. v

3. In a party line selective signaling system, a pair of line wires, a sending station and a plurality of' waystations connected therewith, a pair of relays located at each of said Waystations, the relays of each pair being severally operable by currents over a metallic and grounded circuit including said line wires, resistances in circuit with each relay, the value of the resist-ance in circuit with the relays operable over one circuit increasing in value away from the sending station those in circuit with the relays oper able over the other circuit increasing' in value toward the sending station, a signal at each of said waystations controlled by the relays thereat, and means at the sending station for applying currents to the circuits for operating a selected pair of relays.

4. In a party line selective signaling system, a pair of line wires, a sending station and a plurality of waystations connected therewith, a pair of relays located atl each of said waystations, one operable over a metallic circuit including said line wires, the other over a grounded circuit including said linewires, resistances in circuit with each of said relays operated over said metallic' circuit increasing in value from the sending station outward, resistances in circuit with each of said relays operating over said grounded circuitdecreasing in value from the sending station-outward, and means at the sendingstationfor applying theeurrent to the line wires for.operating,any selected pair of relays. y L.

5. In a party line'selectivesignaling system, a pair of line wires, a sending station and a plurality of waystations connected nieuwe 10 source of current with said circuits through an amount of resistance to impress the proper amount of current upon said circuits to operate a selected pair of relays.

in witness whereof, I hereunto subscribe my namethis 30th day of January A. D., 15

JOHN J. LYNG. Witnesses:

WALTER F. HOFFMAN,

ELLA EDLER. 

